1. Field of the Invention
The present invention relates to a scheme for detecting fraudulent activity related to fuel dispensing transactions, and more particularly to a methodology designed to check independently for fraud without relying on a fuel dispensing meter by relying on tank monitor data.
2. Description of the Related Art
Fuel dispensing transactions are a somewhat opaque process to most customers. The customer drives up, makes a fuel grade selection and dispenses fuel into a vehicle or approved container. When the fuel dispenser shuts off, the customer may check the gauge and see that he owes some amount of money for some amount of fuel dispensed. Alternatively, the customer may only have limited funds and may terminate the transaction upon reaching the budgeted amount as displayed on the face of the fuel dispenser. The financial side of the transaction is completed and the customer drives off.
Behind the scenes, the fuel dispenser is keeping careful track of the amount of fuel dispensed so that it may be displayed to the customer as well as providing a running tally of how much it will cost the customer to purchase the fuel already dispensed. This is typically achieved with a flow meter and a pulser. When a known quantity of fuel has passed through the flow meter, the pulser generates a pulse. Typically, 1000 pulses are generated per gallon of fuel dispensed. The number of pulses may be processed by an internal microprocessor to arrive at an amount of fuel dispensed and a cost associated therewith. These numbers are displayed to the customer to aid him in making fuel dispensing decisions.
Customers of fuel dispensers expect honest and accurate calculations of the cost of fuel actually dispensed into their vehicle and rely on the fuel dispenser display to provide the correct figures. However, unscrupulous individuals may, with little effort, modify the pulser and other internal electronics within the fuel dispenser to provide inaccurate readings, in effect, artificially accelerating the perceived rate of fuel dispensing and charging the consumer for fuel that was not actually dispensed. The mechanisms normally responsible for detecting and preventing this sort of fraud are often the mechanisms that are modified or replaced in the process, completely circumventing any fraud prevention device.
Thus, there remains a need in the field of fuel dispensing to provide an method to detect fraud within fuel dispensing transactions and provide the appropriate alerts to rectify the situation.
The limitations of the prior art are addressed by providing one or more of a matrix of fraud detection schemes that attempt to verify independently of the data reported to the control system the amount of fuel dispensed. If the inferential fuel dispensing observations do not confirm expected fuel dispensing transactions, an alarm may be generated. There are several schemes that could be implemented to detect the fraud.
The first scheme would be to check the vapor recovery system and determine at what rate the vapor was being recovered. Improved monitors allow accurate determinations of how much vapor has been recovered. If the vapor recovered is not comparable to the amount of fuel allegedly dispensed, then fraud may be present. Furthermore, comparing vapor recovery rates between fuel dispensers may also provide a hint that one or more dispensers have been modified to produce fraudulent transactions.
The second scheme includes comparing flow rates between different dispensers. Depending on where the measurement is taken and where the fraud is perpetrated, the flow rate may be higher or lower in the fraudulent dispensers as compared to the nonfraudulent dispensers. However, regardless of where and how, there will be a difference for the fraudulent dispensers.
The third scheme includes measuring the time required to dispense fuel at each dispenser. If one dispenser consistently dispenses fuel at time increments different than other fuel dispenser, it may be a modified dispenser perpetrating a fraud on the unsuspecting customer.
The fourth scheme includes monitoring for increases or decreases in the flow rate at one dispenser that do not occur at other dispensers at the site. The fuel dispenser that has a different performance profile may have been modified. The changes may occur between transactions or even within a single transaction.
The fifth scheme includes using the tank monitor to evaluate how much fuel has been drawn out of the underground storage tank for a given fueling transaction. This can be compared with the amount of fuel that the fuel dispenser reports that it dispensed. If the two numbers are not comparable, then it is likely that the fuel dispenser has been modified.
Other schemes may also be possible, or the schemes presented herein could be expanded or combined so that the fuel dispenser in question is compared not only to other fuel dispensers at the fueling station, but also to some regional or national average for similar fuel dispensers. This may be particularly appropriate where it is a regional or central office that is attempting to detect the fraud and not a single fueling station.